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Calculate 0.71 times 0.53.
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To multiply decimals, first we should ignore the decimal points and the zeros in front of them.
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We will come back to them later.
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Let’s first multiply 71 and 53.
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To begin, we look at the ones place.
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So we have one and three, and one times three is three.
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And again, we found that by multiplying one and three.
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Now we also need to take three and multiply it to the seven, and three times seven is 21.
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So now we need to look at the five.
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And we will take five times one, because of course that’s what we started with the three, and that’s what we will always do.
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So five times one is five.
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However, that five really stands for 53, right?
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So if the five really stands for a 50, we need to put a zero here for a place value holder.
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So five times one is five, and now five times seven is 35.
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And our next step is to add.
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So in the ones, we have three plus zero, which is three, and then one plus five, which is six, five plus two, which is seven.
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And then we have a three.
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So we have 3763.
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Now if we’re multiplying decimals together, it doesn’t make sense to have such a big number.
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Well, the reason why is we need to take care of the decimal point, where should it go.
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To place the decimal point, we must count the number of decimal places in the factors.
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The number of decimal places in the product is equal to that sum.
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The sum of the decimal places in these factors is four, and here’s why.
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We have 0.71 and 0.53.
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Here’s one, two, three, four.
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So there are four decimal places.
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That’s their sum.
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So we must place the decimal point in the product four places from the right.
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So here’s all the way to the right with a decimal point, and we need to place it four places from the right.
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So we’ll need to go to the left: one, two, three, and four.
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So here’s our decimal point.
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And since there’s no number in front, it’s a good idea to put a zero there.
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This makes the decimal point stick out.
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So our final answer will be 0.3763.